1. Field of the Invention
The present invention relates to an apparatus for everting a lining material, and more particularly relates to an apparatus for everting a tubular pipe lining material to repair a deteriorated existing pipe by lining the inner surface thereof.
2. Description of the Prior Art
A pipe lining method has been proposed and is already offered for practical application for cases in which an existing pipe, such as a sewer pipe, a gas pipe, a communication cable duct, an electric power cable duct, and the like, that is buried underground has deteriorated, wherein the existing pipe is repaired by lining the inner surface thereof without digging up the existing pipe.
As one example of the abovementioned pipe lining method, it is known to carry out construction using a pipe lining material made of a tubular resin adsorbing material impregnated with an unhardened liquid setting resin and with the outer surface thereof covered airtightly with a plastic film. With this construction method, a lining eversion apparatus is used to evert and insert a pipe lining material inside the pipeline by fluid pressure and, in a state wherein the pipe lining material is expanded by the fluid pressure and pressed against the inner surface of the pipeline, the setting resin impregnated in the pipe lining material is subsequently cured.
Normally, the pipe lining material is flattened and stored in a sealed container in a folded state. One end of the pipe lining material stored in this sealed container is bent outwardly, attached to the outer circumference of the open end of an eversion nozzle connected to the sealed container, and the lining material is inserted into the pipeline while everting it by the action of the fluid pressure inside the sealed container. Such a method is, for example, disclosed in Japanese Published Patent Application No. 2003-165158.
Nevertheless, the conventional lining material eversion apparatus has a disadvantage in that the pullout resistance during eversion is large and thus requires a large eversion pressure because the pipe lining material is stored so that it is folded in the storage container prior to eversion.
In addition, there is a problem during the pullout in that the pipe lining material of the folded upper part fluctuates vertically with the amount of pullout because the pipe lining material is stored folded, and the pullout is consequently not performed smoothly.
It is therefore an object of the present invention to provide an apparatus for everting a lining material capable of smoothly everting a pipe lining material with little pullout resistance during its eversion.